Diagnostic test tape systems are designed especially for blood sugar tests in order to further improve the user friendliness compared to the test strip systems that are on the market. Thus, in order to simplify the handling, a large number of test units or test fields can be stored on a rollable transport tape in a compact manner and they can also be disposed of again after use by the tape transport. A simple assembly procedure for a test tape of this type is disclosed in EP 1 593 434. Thus, roll-to-roll processing with a high manufacturing speed is possible. In this connection the fabric used as a spreading aid to improve the distribution of the liquid sample is only held by an adhesive layer in the area of its protruding longitudinal edges for process-related reasons. However, if the fabric becomes detached from the detection layer, this can result in a non-uniform wetting with the blood sample which hinders a correct analysis. Furthermore, the spreading fabric may also not become detached from the test field until after the test field has been wetted with blood. The blood then flows into the area of fabric that is still resting on it and forms air bubbles in the separated area of fabric which have a negative effect on the measurement analysis.